In recent years, a technique called a dicing-before-grinding process has been used in order to obtain individual semiconductor chips from a semiconductor wafer on which elements are formed.
In this dicing-before-grinding process, cutting grooves are first formed in a front surface (element formation surface) of the semiconductor wafer (half-cut dicing). Next, after a protection tape is applied on the front surface of the semiconductor wafer in which the cutting grooves are formed, a rear surface of the semiconductor wafer is ground up to the cutting groove portions. Consequently, the thickness of the semiconductor wafer decreases and the semiconductor wafer is divided (separated) into the individual semiconductor chips. On the rear surface of the divided semiconductor wafer, an adhesive film (die-attachment film) is applied to form an adhesive layer, and the protection tape on the front surface (element formation surface) is removed. Then, from the front surface side of the semiconductor wafer, the adhesive layer is cut along the dividing grooves by a diamond blade, a laser, or the like. Consequently, the semiconductor chips with the adhesive layer are obtained. This semiconductor chip with the adhesive layer is thereafter picked up by a sucking tool called a collet and is stacked and bonded on a substrate or another semiconductor chip.
In this method, however, since an alignment state of the semiconductor chips after the protection tape is removed is not good, there are possibilities that, when the adhesive film is cut, wiring regions of the elements might be partly cut and the surfaces might get dirty due to cutting chips, or when the semiconductor chips are picked up after the cutting, the chips might be cracked due to a load and thermal welding at the time of the cutting.